Math Revisited, Again

My parents lent us the Great Courses Algebra video and workbook.  I have no answer book for the workbook, and so it was becoming a challenge to grade.  I really don't have the time to go through the videos and do the work myself in order to have an answer for all of his work.  I feel horrible about this.  With that in mind, however, we did go ahead and make the switch to Teaching Textbooks.  G said that the problems in there were easy peasy compared to what he had been doing, so I'm tempted to have him do the Great Courses while we're staying at houses, just to give him that extra exposure to more complex ideas, by without me grading them.  I need to have a way to keep track of his progress in math, I need to know he's getting the concepts the book is trying to get across to him, and I simply can't do that if I have to do all the work alongside him just to make sure he's got the correct answer.  I've got so much going on, that's just not working for me.  I feel a bit of a failure on this one...